The subject matter disclosed herein relates to power plant systems and, more particularly, to steam turbine operation in power plant systems.
Some power plant systems, for example certain nuclear, fossil fuel, solar, simple-cycle and combined-cycle power plant systems, employ turbines (e.g., steam turbines, gas turbines, etc.) in their design and operation. Some turbines in these systems are connected to a condenser which during operation may cool portions of and/or fluids within the turbine via a cooling fluid. This cooling by the condenser may lower exhaust pressure in the turbine, thereby improving the output and heat rate of the turbine and the overall power generation system. Some condensers circulate the cooling fluid about the turbine to transfer heat from the turbine to the cooling fluid. In these condensers, as a temperature of the cooling fluid is decreased relative to a temperature of the fluids and components of the turbine, the cooling process and overall system efficiency is improved. Some systems include cooling towers which are connected to the condensers to supply and refrigerate the cooling fluid, reducing a temperature of the cooling fluid so as to improve the cooling process. However, the use of these cooling towers may result in inconsistent cooling fluid temperatures and cooling fluid availability which leads to variable exhaust pressure in the steam turbine, and thus inefficient operation.